The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Vehicles, including, but not limited to, hybrid engine vehicles, may include engine start-stop functionality that stops and starts an internal combustion engine to limit the idle time of the internal combustion engine. For example, the internal combustion engine may be stopped and restarted when the vehicle is not in motion in order to improve fuel economy.
Typically, while the engine is off, thermal energy from the combustion chamber is directed to other system components, such as a cabin heater. Removing thermal energy from the combustion chamber cools cylinder walls and has a damaging effect on fuel efficiency. For example, the engine may be restarted while the engine is cool, resulting in lowered fuel efficiency while the engine warms. Accordingly, a system that meets heating and cooling needs of the vehicle while maximizing cylinder wall temperature and maintaining fuel efficiency benefits is desired.